18079729 has 8 divisors (see below), whose sum is σ = 18826920. Its totient is φ = 17347200.

The previous prime is 18079709. The next prime is 18079739. The reversal of 18079729 is 92797081.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 565504 + 17514225 = 752^2 + 4185^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18079729 - 2¹⁷ = 17948657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18079709) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1114 + ... + 6115.

It is an arithmetic number, because the mean of its divisors is an integer number (2353365).

Almost surely, 2^18079729 is an apocalyptic number.

It is an amenable number.

18079729 is a deficient number, since it is larger than the sum of its proper divisors (747191).

18079729 is an equidigital number, since it uses as much as digits as its factorization.

18079729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7331.

The product of its (nonzero) digits is 63504, while the sum is 43.

The square root of 18079729 is about 4252.0264580550. The cubic root of 18079729 is about 262.4605122764.

The spelling of 18079729 in words is "eighteen million, seventy-nine thousand, seven hundred twenty-nine".